1 /*
2  * Copyright (C) 2019 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include <android-base/logging.h>
18 #include <android/hardware/automotive/can/1.0/ICanBus.h>
19 #include <android/hardware/automotive/can/1.0/ICanMessageListener.h>
20 #include <android/hidl/manager/1.2/IServiceManager.h>
21 #include <hidl-utils/hidl-utils.h>
22 
23 #include <linux/can.h>
24 #include <chrono>
25 #include <iomanip>
26 #include <iostream>
27 #include <string>
28 #include <thread>
29 
30 namespace android::hardware::automotive::can {
31 
32 using namespace std::chrono_literals;
33 
34 using ICanBus = V1_0::ICanBus;
35 using Result = V1_0::Result;
36 
37 struct CanMessageListener : public V1_0::ICanMessageListener {
38     const std::string name;
39 
CanMessageListenerandroid::hardware::automotive::can::CanMessageListener40     CanMessageListener(std::string name) : name(name) {}
41 
onReceiveandroid::hardware::automotive::can::CanMessageListener42     virtual Return<void> onReceive(const V1_0::CanMessage& message) {
43         int msgIdWidth = 3;
44         if (message.isExtendedId) msgIdWidth = 8;
45         std::cout << "  " << name << "  " << std::hex << std::uppercase << std::setw(msgIdWidth)
46                   << std::setfill('0') << message.id << std::setw(0);
47         std::cout << "   [" << message.payload.size() << "] ";
48         if (message.remoteTransmissionRequest) {
49             std::cout << "remote request";
50         } else {
51             for (const auto byte : message.payload) {
52                 std::cout << " " << std::setfill('0') << std::setw(2) << unsigned(byte);
53             }
54         }
55         std::cout << std::nouppercase << std::dec << std::endl;
56         return {};
57     }
58 
onErrorandroid::hardware::automotive::can::CanMessageListener59     virtual Return<void> onError(V1_0::ErrorEvent error) {
60         std::cout << "  " << name << "  " << toString(error) << std::endl;
61         return {};
62     }
63 };
64 
usage()65 static void usage() {
66     std::cerr << "canhaldump - dump CAN bus traffic" << std::endl;
67     std::cerr << std::endl << "usage:" << std::endl << std::endl;
68     std::cerr << "canhaldump <bus name>" << std::endl;
69     std::cerr << "where:" << std::endl;
70     std::cerr << " bus name - name under which ICanBus is be published" << std::endl;
71 }
72 
73 // TODO(b/135918744): extract to a new library
tryOpen(const std::string & busname)74 static sp<ICanBus> tryOpen(const std::string& busname) {
75     auto bus = ICanBus::tryGetService(busname);
76     if (bus != nullptr) return bus;
77 
78     /* Fallback for interfaces not registered in manifest. For testing purposes only,
79      * one should not depend on this in production deployment. */
80     auto manager = hidl::manager::V1_2::IServiceManager::getService();
81     auto ret = manager->get(ICanBus::descriptor, busname).withDefault(nullptr);
82     if (ret == nullptr) return nullptr;
83 
84     std::cerr << "WARNING: bus " << busname << " is not registered in device manifest, "
85               << "trying to fetch it directly..." << std::endl;
86 
87     return ICanBus::castFrom(ret);
88 }
89 
candump(const std::string & busname)90 static int candump(const std::string& busname) {
91     auto bus = tryOpen(busname);
92     if (bus == nullptr) {
93         std::cerr << "Bus " << busname << " is not available" << std::endl;
94         return -1;
95     }
96 
97     Result result;
98     sp<V1_0::ICloseHandle> chnd;
99     // TODO(b/135918744): extract to library
100     bus->listen({}, new CanMessageListener(busname), hidl_utils::fill(&result, &chnd)).assertOk();
101 
102     if (result != Result::OK) {
103         std::cerr << "Listen call failed: " << toString(result) << std::endl;
104         return -1;
105     }
106 
107     while (true) std::this_thread::sleep_for(1h);
108 }
109 
main(int argc,char * argv[])110 static int main(int argc, char* argv[]) {
111     base::SetDefaultTag("CanHalDump");
112     base::SetMinimumLogSeverity(android::base::VERBOSE);
113 
114     if (argc == 0) {
115         usage();
116         return 0;
117     }
118 
119     if (argc != 1) {
120         std::cerr << "Invalid number of arguments" << std::endl;
121         usage();
122         return -1;
123     }
124 
125     return candump(argv[0]);
126 }
127 
128 }  // namespace android::hardware::automotive::can
129 
main(int argc,char * argv[])130 int main(int argc, char* argv[]) {
131     if (argc < 1) return -1;
132     return ::android::hardware::automotive::can::main(--argc, ++argv);
133 }
134